The present invention relates to catheters, and more particularly to hemostatic catheters.
In certain male patients it may be necessary to remove the prostate in the event that it becomes fibroid or cancerous. Generally, the prostate is removed either through a suprapubic procedure or a transurethral dissection during which a cystoscope is utilized to carve out the prostate. After the prostate has been removed, the cystoscope is withdrawn from the patient leaving a bleeding cavity or prostatic fossa adjacent the bladder where the prostate was formerly located.
In the past, the urologists have stopped the bleeding over a period of time in the following manner. A catheter having a balloon adjacent a distal end of the catheter shaft is passed through the urethra until the balloon is located in the bladder and a proximal end of the catheter is located outside the patient. The removed prostate is weighed to estimate the size of the prostatic fossa in the particular patient, and a quantity of fluid proportional to the prostatic weight is pumped into the catheter balloon in order to inflate the balloon in the bladder a sufficient amount to later prevent the balloon from falling into the prostatic fossa. Next, force is applied against the catheter shaft such that the balloon in turn applies pressure against the apex of the incised blood vessels, with the pressure being maintained for a period of time which may vary from five minutes to twenty four hours depending upon the preference of the particular urologist. The amount of force applied to the catheter by pulling its proximal end also varies with the urologist, but is believed equivalent to the force caused by a weight in the range of from 1-12 lbs. if such weight was attached to the proximal end of the catheter.
In this manner the bleeding is eventually stopped, although the procedure is accompanied by a great amount of uncertainty. Initially, the urologist does not have any clear indication from experience concerning the amount of force which is desired to stop bleeding, and, even if known, the urologist could not determine whether the desired amount of force is being applied to accomplish hemostasis unless actual weights are attached to the proximal end of the catheter shaft. In this regard, it is necessary to apply sufficient force against the catheter to obtain hemostasis, yet undue pressure by the inflated balloon against the blood vessels in the bladder may result in pressure necrosis and must be prevented.
Thus, it is desirable to provide the urologist with a convenient indication of the applied forces and pressures, in order that he can determine through experience the proper range of forces required for hemostatis while preventing pressure necrosis in the bladder. Once such range has been ascertained, it is desirable that the urologist may readily determine whether the proper amount of force is being applied against the catheter during a particular procedure without the inconvenience of hanging weights from the catheter.